Judges on Thursday refused the Lockerbie bomber's family permission to take an appeal against his conviction to the UK's highest court.
The bombing of Pan Am flight 103, travelling from London to New York on December 21, 1988, killed 270 people in Britain’s deadliest terrorist attack.
Former Libyan intelligence officer Abdelbaset Al Megrahi was found guilty in 2001 of mass murder and sentenced to life in jail with a minimum term of 27 years – the only person convicted of the attack.
In January, judges at the Court of Appeal in Edinburgh rejected a third appeal against his conviction made by his son.
Lawyers acting for the Megrahi family then sought permission to appeal to the UK Supreme Court, the final court of appeal for the case, but this was refused by five Scottish judges.
Family lawyer Aamer Anwar said they will now seek leave to appeal directly to the UK Supreme Court.
A written judgment issued on Thursday by Lord Carloway, the Lord Justice General, said the court “has had some difficulty in understanding the exact nature of the challenge”.
“Although the case is clearly one of public importance, the proposed grounds of appeal do not raise points of law of general public importance.
“The principles of law which the court applied were all well known, settled and largely uncontroversial in the appeal.
“For these reasons, the court refuses permission to appeal to the UK Supreme Court.”
Megrahi was released from prison in 2009 on compassionate grounds while terminally ill with cancer, and died in Libya in 2012.
The third appeal was lodged after the Scottish Criminal Cases Review Commission referred the case to the High Court in March 2020, ruling a possible miscarriage of justice may have occurred.
Judges then granted his son, Ali Al Megrahi, permission to proceed with the appeal in relation to the argument that “no reasonable jury” could have returned the verdict the court did, and on the grounds of non-disclosure of documents by the Crown.
Appeal court judges in January rejected both grounds of appeal, meaning the conviction stands.
“It is time for a new Libya, but that will never happen until there is justice for those who died in Lockerbie. I regard my father Abdelbaset Al Megrahi as the 271st victim of Lockerbie," Ali Al Megrahi said.
"[Libya now has] a new democratic government and we look to them to support our legal team in their pursuit of justice."